Beeradvocate. They have two version of it.. One that they bottle and send out, and another that they serve in their brewpub only.

The blend doesn't have to be exactly. There is a bit of "marketing" that goes along with it to make it all match up.

50/50 is close, but it's more 90 in there if you go the route of blending.

Dump half a 90/60 from a bottle in a glass. It doesn't taste like the 75min does in the bottle.

I'm doing a clone of this, and there's actually a YouTube video review from a beer club where Sam is in attendance. He says on the video that it's 50/50 of both. Whether that differs in the commercial product.....well who cares. I'd just blend 50/50 and forget about it. Also, the blend is then dry hopped additionally with Cascade, which may contribute to your differentiation of the 2 products, not to mention time for flavors to meld, etc. Mixing 2 bottles and immediately drinking is in no way the same.